DS90CR213_05 Datasheet, PDF (1/15 Pages) Texas Instruments – 21-Bit Channel Link-66 MHz

August 2005
DS90CR213/DS90CR214
21-Bit Channel Link—66 MHz
General Description
The DS90CR213 transmitter converts 21 bits of CMOS/TTL
data into three LVDS (Low Voltage Differential Signaling)
data streams. A phase-locked transmit clock is transmitted in
parallel with the data streams over a fourth LVDS link. Every
cycle of the transmit clock 21 bits of input data are sampled
and transmitted. The DS90CR214 receiver converts the
LVDS data streams back into 21 bits of CMOS/TTL data. At
a transmit clock frequency of 66 MHz, 21 bits of TTL data are
transmitted at a rate of 462 Mbps per LVDS data channel.
Using a 66 MHz clock, the data throughput is 1.386 Gbit/s
(173 Mbytes/s).
The multiplexing of the data lines provides a substantial
cable reduction. Long distance parallel single-ended buses
typically require a ground wire per active signal (and have
very limited noise rejection capability). Thus, for a 21-bit wide
data and one clock, up to 44 conductors are required. With
the Channel Link chipset as few as 9 conductors (3 data
pairs, 1 clock pair and a minimum of one ground) are
needed. This provides an 80% reduction in required cable
width, which provides a system cost savings, reduces con-
nector physical size and cost, and reduces shielding require-
ments due to the cable’s smaller form factor.
The 21 CMOS/TTL inputs can support a variety of signal
combinations. For example, 5 4-bit nibbles (byte + parity) or
2 9-bit (byte + 3 parity) and 1 control.
Features
n 66 MHz Clock Support
n Up to 173 Mbytes/s bandwidth
n Low power CMOS design (<610 mW)
n Power-down mode (<0.5 mW total)
n Up to 1.386 Gbit/s data throughput
n Narrow bus reduces cable size and cost
n 290 mV swing LVDS devices for low EMI
n PLL requires no external components
n Low profile 48-lead TSSOP package
n Rising edge data strobe
n Compatible with TIA/EIA-644 LVDS Standard
Block Diagrams
DS90CR213
DS90CR214
Order Number DS90CR213MTD
See NS Package Number MTD48
01288827
01288801
Order Number DS90CR214MTD
See NS Package Number MTD48
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